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<div class="titlepage"><div><div><h3 class="title">
<a name="math_toolkit.float128.typeinfo"></a><a class="link" href="typeinfo.html" title="typeinfo"><code class="computeroutput"><span class="identifier">typeinfo</span></code></a>
</h3></div></div></div>
<p>
        For GCC 4.8.1 it was not yet possible to use <code class="computeroutput"><span class="identifier">typeinfo</span></code>
        for <code class="computeroutput"><span class="identifier">float_128</span></code> on GCC: see
        <a href="http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43622" target="_top">GCC 43622</a>.
      </p>
<p>
        So this code (to display the mangled name) failed to link <code class="computeroutput"><span class="identifier">undefined</span>
        <span class="identifier">reference</span> <span class="identifier">to</span>
        <span class="identifier">typeinfo</span> <span class="keyword">for</span>
        <span class="identifier">__float128</span></code>
      </p>
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="keyword">typeid</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">float128_t</span><span class="special">).</span><span class="identifier">name</span><span class="special">()</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
</pre>
<p>
        This prevent using the existing tests for Boost.Math distributions, (unless
        a few lines are commented out) and if a MACRO BOOST_MATH_INSTRUMENT controlling
        them is defined then some diagnostic displays in Boost.Math will not work.
      </p>
<p>
        However this was only used for display purposes and could be commented out
        until this was fixed in GCC 5.
      </p>
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          Not all managed names can be <span class="bold"><strong>displayed</strong></span>
          using <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span></code>.
        </p></td></tr>
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